Collaborative Research RUI: Examination of the Effect of Templating Agents on the Size, Shape and Chiral Recognition of Bifurcated Amino Acid Based Amphiphilic Molecular Assemblies

在化学系大分子、超分子和纳米化学计划的支持下，德克萨斯A&M大学语料库的Eugene Billiot、Fereshteh Billiot和Mark Olson(TAMUCC)以及他们在迦太基学院的合作者Kevin Morris将合成并表征一类新型的基于氨基酸的“支化”表面活性剂。这项研究的目标是了解导致这些分子聚集和自组装成结构的分子因素，这些结构将与具有生物重要性的分子相互作用并识别。表面活性剂的合成将使用绿色化学方法，其中材料将由基于氨基酸的原料制备，而不是潜在危险的多芳烃。此外，由于表面活性剂是以氨基酸为基础的，它们有望具有生物相容性。这项研究将有助于填补当前知识库中的一个空白，这对于正确设计和选择更有效的手性选择剂至关重要。此外，由于正在研究的体系的对映体识别是基于氨基酸支架，从这些研究中获得的知识将有可能转移到其他基于氨基酸的体系，如蛋白质。这个项目是两个主要是本科生的机构之间的合作，其中一个机构，TAMUCC，是一个为西班牙裔服务的机构(HSI)。因此，由这笔拨款资助的研究将成为研究团队的工具，以招收、培训和指导来自代表性不足和经济困难背景的学生，并鼓励这些学生攻读理科学士学位。研究重点是调查和阐明导致(A)自组装、(B)功能、(C)更高有序结构和(D)基于氨基酸的大分子组件(AABMA)的分子识别的因素。比较了“线型”AABMA和新型“分叉型”AABMA的性质，以及表面活性剂浓度、表面活性剂类型(线型和分叉型)、pH和反离子/模板剂类型等因素如何影响AABMA的大小、形状、物理性质和对映体识别。AABMA将以单体和聚合物的形式进行研究。AABMAs胶束将通过暴露在Co60伽马辐射或185 nm真空紫外线辐射下进行交联。研究了pH、反离子/模板剂和表面活性剂浓度对聚合、自组装、功能、高阶结构和分子识别的影响。将利用各种技术，如核磁共振(核磁共振)、荧光、小角中子散射(SANS)、小角X射线散射、低温透射电子显微镜、动态光散射方法以及毛细管电泳法(CE)来更多地了解形成的AABMA的物理性质。将进行热力学研究，以深入了解表面活性剂/聚合物胶束的手性分子识别单元与将用于滴定微量热法手性分离的手性分析物之间的结合作用。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Eugene Billiot, Fereshteh Billiot and Mark Olson of Texas A&M University Corpus Christi (TAMUCC), along with their collaborator Kevin Morris at Carthage College, will synthesize and characterize a novel class of “branched” amino acid-based surfactants. The goal of the research is to understand the molecular factors responsible for the aggregation and self-assembly of these molecules into structures that will interact with and recognize molecules of biological importance. Synthesis of the surfactants will use a green chemistry approach where materials will be prepared from amino acid-based starting materials instead of potentially hazardous polyaromatic hydrocarbons. Furthermore, since the surfactants are amino acid-based, they are expected to be biocompatible. The research will help fill a void in the current knowledge base that is critical for the proper design and selection of more efficient chiral selectors. In addition, since enantiorecognition of the systems under study is based upon amino acid-scaffolding, the knowledge gained from these studies will be potentially transferable to other amino acid-based systems such as proteins. This project is a collaboration between two primarily undergraduate institutions, with one of those two institutions, TAMUCC, being a Hispanic-serving institution (HSI). Thus, the research to be funded by this grant will serve as a tool for the research team to recruit, train, and mentor students from underrepresented and economically challenged backgrounds and to encourage these students to pursue post baccalaureate degrees in science.The research is focused on investigating and elucidating the factors responsible for (a) self-assembly, (b) function, (c) higher ordered structure and (d) molecular recognition of amino acid-based macromolecular assemblies (AABMAs). A comparison of the properties of “linear” AABMAs to novel “bifurcated” AABMAs will be made and how they are affected by factors such as surfactant concentration, surfactant type (linear vs bifurcated), pH, and type of counterion/templating agent affect the size, shape, physical properties, and enantiomeric recognition of AABMAs. The AABMAs will be studied in both their monomeric and polymeric forms. The AABMAs micelles will be crosslinked by exposure to Co60 gamma radiation or 185 nm vacuum UV radiation. The effect of pH, counterion/templating agent, and surfactant concentration on polymerization, self-assembly, function, higher order structure and molecular recognition will be studied. A variety of techniques such as nuclear magnetic resonance (NMR), fluorescence, Small Angle Neutron Scattering (SANS), small angle X-ray scattering, cryo-transmission electron microscopy, dynamic light scattering methods, as well as capillary electrophoresis (CE) will be utilized to learn more about the physical properties of the AABMAs formed. Thermodynamic studies will be conducted to yield insight into the binding interactions between the chiral molecular recognition units of the surfactants/polymer micelles and the chiral analytes that will be targeted for chiral separations using titration microcalorimetry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.